An empty space is seen on October 16, 2012 where a painting by French artist Henri Matisse was stolen at the Kunsthal museum in Rotterdam a day after seven masterpieces worth up to 200 million euros were stolen from the museum in a pre-dawn heist. A 19-year-old Romanian woman has been arrested in Rotterdam in the art heist probe, Dutch police said on March 4, 2013. AFP PHOTO / ANP / ROBIN UTRECHT.

THE HAGUE(AFP).- Dutch prosecutors will not ask Bucharest to extradite the suspects in a spectacular art theft from a Rotterdam museum last year, saying on Thursday it was a Romanian matter.

"The Public Prosecution is not planning to ask for the extradition of the suspects who are currently in custody," it said in a statement issued from Rotterdam.

"The suspects are being prosecuted in Romania, it is a Romanian investigation and because they are Romanian," the prosecutor's office gave as reasons for its decision.

Seven Romanians have so far been charged in connection with the lightning robbery of the seven masterpieces from Rotterdam's Kunsthal Museum in October last year.

Four are currently in custody in Romania, one has been charged but remains free and another is on the run. A Romanian woman has also been charged in the Netherlands.